Bag making machine



Aug. 16, 1938. A. POTDEVIN BAG MAKING MACHINE Original Filed March 14,1935 2 Sheets-Sheet l um I INVENTOR BY p 0 wflzlzzy ATTORNEYS,

Aug. 16, 1938.

A. POTDEVIN,

BAG MAKING MACHINE Original Filed March 14, 1935 2 Sheets-Sheet 2NVENTOR Patented Aug. 16, 1938 PATENT OFFICE BAG MAKING MACHINE AdolphPotdevin, Garden City, N. Y., assignor to Potdevin Machine Company,Brooklyn, N. Y., a corporation oi New York Original application March14, 1935, Serial No.

Divided and this application August 20, 1936, Serial No. 96,914

4 Claims. (Cl. 938) This invention is directed to an improved method andapparatus for making bags and is particularly directed to the making ofbags of the satchel bottom type from cellulose or other light-weightmaterial.

The present application is a division of my copending application SerialNo. 10,968, filed March 14, 1935, Bag making machine.

Primarily the present application is directed to a method and apparatusfor cutting and creasing a bag tube preparatory to the formation of thebottom thereon.

In the accompanying drawings:

Fig. 1 is a sectional elevational view of the cutting and creasingmechanism for operating on the bag tube before the same reaches thebottoming drum;

Fig. 2 is a plan view of the mechanism of Fig. 1;

Fig. 3 is a sectional elevational view of improved cross-scoringmechanism;

Fig. 4 is a view in part sectional elevation of mechanism which engagesor grips the leading end of a bag length as the same comes up to thebottoming drum;

Fig. 5 is a part sectional elevational view of another form ofcross-scoring mechanism;

Fig. 6 is an elevational view of the mechanism of Fig. 5; and

Fig. 7 is a view of a bag length after it has been slit at the lip orleading end and as it appears after being scored by the scoringmechanism of Fig. 3, for instance.

Referring to the drawings in detail, the material to be handled by thepresent apparatus is taken from a roll in the usual fashion and fedthrough tubing mechanism which forms the web into a tube. The tubedmaterial is designated I.

The tubed material is advanced continuously and in a continuous lengthand is divided into bag lengths by the mechanism shown at 2. Thismechanism is similar to the cutting of! mechanism constituting thesubject matter of Paul Hunziker copending application Serial No.647,502. However, the cut-off mechanism may be of any conventionalconstruction. The cutting of! mechanism cuts the tubing into bag lengthsleaving a lip 3 at the leading end of the bag length or bag blank and alip 4 at the trailing end. A, bag length is shown in Fig. 7 where it hasbeen designated 5.

During the cutting off operation the tubing is engaged by pinch rollers6 and l and lies at this time between the upper face of a plate 8 andadjustable hold-down fingers 9 carried by rods I0 secured to the machineframe.

As the tube is divided into bag lengths the leading end of each lengthpasses between slitting and scoring mechanism shown at II and I2 in Fig.1 to slit the leading end of each bag length through both walls thereofas shown at A and B in Fig. 7 for instance and to cross score the baglength as shown at CS in the same figure.

In the usual bag machine for converting ordinary bag paper into bags, itis usual to equip the machine with a cylinder having a longitudinalgroove therein cooperating with a scoring knife in an opposed cylinderto cross score the bag tube or bag length for the main bottom fold.Owing to the natural springiness or elasticity of materials such ascellophane for which my machine is particularly well adapted such crossscoring mechanism fails to score the bag length satisfactorily and if,in order to obtain a well defined score with such mechanism, the partsare set closer together than when handling ordinary bag paper there isalways danger of cutting the material instead of scoring it with aresultant increase in waste of material. The present invention providesfor eliminating these difficulties.

As clearly shown on the drawings, particularly Figs. 2 and 3, thescoring mechanism of. this invention comprises a thin scoring blade I3preferably mounted on a shaft I4 rotatably adjustable in discs I5 on ashaft IS. The discs I5 are adjustable circumferentially of the shaft I6,as will be apparent from Fig. 2. The scoring blade I3 which depressesthe bag blank or bag length out of the plane of the surface of the blankin a transverse area cooperates with a cam-and-spring operated movablejaw I'I carried by a shaft I8 having bearings in the end walls of acircumferentially adjustable disc cylinder I9 mounted below the discs I5on a shaft I9.

The cam and spring for operating the jaw I! are designated 20 and 2 I,respectively. The lower disc cylinder I9 carries an abutment 22 whichcooperates with the movable jaw H, the abutment and jaw constitutingcompression jaws. The face of the jaw I1 is cut back at an angle as seenin Fig. 3 and in operation the blade [3 depresses the wall of the baglength between the jaw I! and abutment 22 before the jaw closes andinasmuch as on continued rotation of the discs I5 and lower cylinder I9the blade I3 is withdrawn the blade is followed up by the jaw I! whichsharply grips the tucked-in portion of the bag length at'the apex 23only, as seen in Fig. 3, instead of the entire face of the jaw clampingthe material between it and the abutment 22 in a manner similar to thatemployed in clamping devices generally scoring CS is prevented.

used heretofore. By sharply pinching only the apex 23 of the tucked-inportion of the bag length I provide a permanent transverse or crossscore CS in the material despite the natural springiness or elasticityof the same. At the same time I avoid cutting of the material so as toeliminate all waste from the cross scoring operation.

Two of the discs I5, which in addition to being adjustablecircumferentially are adjustable longltudinally of the shaft I5, areprovided with slitting knives 24 for slitting the bag lengths at A andB, these slitting knives as will be seen from Fig. 1 being adjustablecircumferentially relatively to the shaft I6 and cooperating with thelower discs l9 which are also adjustable longitudinally of theirsupporting shaft I9 so as to adapt the machine for proper adjustment toslit bag lengths of different'sizes, as will be understood.

The slitting operation, as will be seen from Fig. 1, precedes the crossscoring operation.

During the slitting and scoring operations the bag length underliesadjustable hold-down fingers 25 carried by vertically extending posts 26mounted on the machine frame.

Inasmuch as there is no other operation to be performed at this pointthe scoring clamp I1 releases the tube immediately after the crossscoring operation is completed and the bag tube is forwarded by therotated scoring mechanism to the next station of operation between discs21 and cooperating lower cylinder 28, passing between hold-down fingers25 and plate 29.

As the leading end of the bag length reaches r this next station ofoperation the cam-and-spring operated gripper 30 carried by one of thediscs 21 takes hold of the upper ply of the bag length at the point 3I,Fig. 7, between the slits A clamping it against a cooperating abutment32 on a shaft 33 on which the discs 21 are mounted.

As the bag length passes between the discs 21 and the cylinder 28 thegripper 30 will be in open position-as shown in'Fig. 4, so that the noseof .the gripper will enter-the open end of the tube, and the projectinglip 3 on the lower wall of the tube will be' pushed downwardly, asillustrated in Fig. 4, bending the same over the edge of an abutment 34on the shaft 35 carrying the lower cylinder 28. This portion of thelower wall of the tube springing back against the back of the gripper30as the gripper clamps or grips the upper wall of the tube against theabutment 32. The abutment 34 is adjustable circumferentially of theshaft 5, as will be seen from Fig. 4.

Pivotally mounted on the discs 21 is a shaft 36 carrying a blade 31. Oneend of this shaft. 36 is equipped with a lever and cam follower roller38 and with a suitable spring 39 to keep this roller in contact with anadjustable stationary cam 40. The function of the cam 4|] is to causethe blade 31 to swing outwardly beyond the periphery of the discs 21 atthe proper instant to push the scored area of the bag length away fromthe surface of the discs 21 and toward the large bottom opening drum Hwhich carries grippers-52 for gripping the lip 3 of the bag length.Intliis way pulling open the bag length beyond the cross The gripper 30heretofore referred to is mounted on a shaft 42 and is controlled by acam 43.

The hold-down fingers 25, referred to above, extend from a point at therear of the slitting and scoring station to a point between the discs 21and cylinder 28.

Between the scoring station and the station just referred to I provide arock shaft 44 carrying fiat spring-like fingers 45 extending forwardlyand downwardly between the hold-down fingers 25. Theshaft 44 is rockedby a cam 46, cam follower 41 carried by the shaft 44 being held inengagement with this cam by a spring 48. The fingers 45 remain in araised position during the progress of the tube 5 from the scoringstation to the gripper or clamping station un til the lip 3 on theleading end of the tube or bag length has been gripped by the gripperson the bottoming cylinder M, at which time the cam 46 will be inposition to move these spring fingers 45 downwardly toward the lowerguide plate 29 to hold the tube or bag length with a slight springpressure against the guide plate, the spring fingers continuing to holdthe bag length in contact with this plate approximately until thegripper 30 is ready to release the leading end of the upper ply of thebag length, it being borne in mind that the leading end of the upper plyof the bag length is gripped at this time by gripper 30 as aboveexplained.

The fingers 45, therefore, exert a slight frictional hold-back actionupon the bag length 5 during the first stages of opening the leading endof the bag length in the bottoming operation, thereby insuring that thebag length 5 will lie fiat on the bottoming drum 4| so that thepreviously made score CS will always be in the cor,- rect position forthe blade 31 to act on as previously claimed.

In Figs. 5 and 6 I have shown a modified form of cross scoringmechanism, the cross scoring blade I3 instead of being mounted on anadjustable shaft I4 is mounted in the discs I5 on the shaft I6. Thecross scoring blade is adapted to be reciprocated vertically in thediscs I5 by springs I05 and cam I06. The scoring jaw I1 iscam-and-sp'ring operated and, as in the case of Fig. 2, this jaw Il'cooperates with an abutment 22'. The parts are so timed and discs I5 andI9 are so relatively positioned that as the scoring blade I3 is broughtinto position to engage a bag length 5 the scoring blade will be in itsoutermost position in the discs IS, the blade at that time riding on thehigh partof the cam I06. As the parts reach'the position shown in Fig. 5or on a slightly further advanced position than shown in this figure,the cross scoring blade I3 will ride off the high part of the cam I06 soas to be moved inwardly of the discs I5 by the action of the spring I05,permitting the jaw IIf to close on the material of the bag length whichhas been inserted between the jaw I1 and the abutment 22' by the crossscoring blade to allow the jaw to grip the apex of this depressedportion of the bag length as described in connection with my descriptionof the apparatus shown in detail in Fig. 3. In other words, just as thecross scoring blade I3 is retracted out of the space between the jaw I1and abutment 22' the jaw will close.

It is to be understood that the construction and operation of thebottomingmechanism constitutes no part of the present application, thesame beingshown, described and claimed in my copending applicationSerial No. 10,968 of which the present application is a division;

What I claim is:-

1. In a bag machine, the combination of cutting-off mechanism fordividing continuously advancing bag tubing into bag lengths, hold-backmechanism following the cutting-off mechanism and cooperating therewith,slitting and crossscoring mechanism following" the hold-back mechanism,and hold-down fingers for engaging the upper face of the bag lengths intheir passage to the slitting and scoring mechanism.

2. In a bag machine, cross-scoring mechanism comprising in combination ascoring blade for depressing the area of a bag blank to be scored and apair of scoring jaws for receiving the depressed area of the blank, theactive face of one of said jaws being sloped away from the other jawwhereby only the apex of the depressed portion of the bag blank will begripped by the jaws.

3. In a bag machine, cross-scoring mechanism comprising in combination ashaft extending transversely of the machine, rotatable means carryingsaid shaft, said rotatable means being circumferentially adjustable andsaid shaft being circumferentially adjustable in said rotatable means, ascoring blade carried by said shaft and adapted to be carried by saidrotatable means into engagement with the face of a traveling bag blankto depress the bag blank in an area extending transversely of the blank,a pair of scoring jaws, rotatable means carrying said jaws, one of saidjaws being pivoted, cam and spring mechanism for opening and closingsaid jaws, said cam and spring mechanism being so timed with respect tothe timing of the scoring blade that the area depressed by the bladewill be gripped by said jaws, the opposed or activefaces of the jawsbeing so shaped that only the apex of the depressed area of the bagblank will be gripped upon closure of the scorer jaws.

4. In a bag machine, cross-scoring mechanism for cross-scoring bagblanks comprising in combination scoring blade, rotatable means carryingsaid blade, a cam for moving said blade outwardly radially of saidrotatable means, a spring for retracting said blade, a pair of scoringjaws cooperating with said scoring blade, rotatable means carrying saidjaws, said scoring blade on the advance of a bag blank between saidrotatable means being held in position by said cam so as to engage thebag blank to depress the same in an area extending transversely of theblank into position between said'jaws, said scoring blade beingretracted by said spring on further advance of the bag blank to permitsaid jaws to close upon the bag blank, the active face of one of saidjaws sloping away from the active face of the cooperating jaw so as toapply a squeeze to the depressed portion of the bag blank which isconfined to the apex thereof.

ADOLPH PO'I'DEVIN.

